Gardening Articles: Flowers :: Bulbs

Sweet Summer Bulbs (page 2 of 3)

by Charlie Nardozzi

Dahlias

Dahlia

There is nothing subtle about dahlias. The intense colors and huge flowers of many dahlia varieties can dominate a garden. Dig a 6- to 12-inch-deep hole depending on the size of the tuber. Plant tubers 2 to 4 inches deep and 1 to 3 feet apart. Deadhead spent flowers to keep the plants producing blooms until frost. Since dahlias are only hardy to USDA zone 8, in colder regions you'll need to dig tubers after frost has blackened the foliage. Let them dry, then store the tubers in boxes filled with slightly moistened peat moss in a well-ventilated, cool (45 to 55 degrees F.) basement.

"Dinnerplate" dahlias are large, 3- to 4-foot-tall plants with 10- to 12-inch-diameter blossoms. Stake these so they don't flop over in summer. Medium-sized (1 to 2 feet tall) dahlias include "border" and "cactus" types. Diminutive dahlias, such as 'Mignon', grow only 10 to 12 inches tall, but their small, colorful flowers look great in containers.

Gladiolus

Gladiolus

Gladiolus produce classic flower spikes in all the colors of the rainbow. These 3- to 4-foot-tall plants are mostly grown as cut flowers. Most are hardy to USDA zone 7, but hardy gladiolus (Gladiolus byzantinus), which produce smaller plants and flowers, are hardy to zone 5.

Plant corms 2 to 6 inches deep (depending on their size) and 6 inches apart. Since gladiolus grow tall, hill the soil around young plants, and stake them when they reach a few feet tall to prevent them from toppling over. Side-dress with a complete fertilizer when plants are 8 to 12 inches tall.

Choose gladiolus varieties based on flower color and shape. 'Rainbow' and 'Butterfly' are two popular mixes. When you cut the flowers, leave at least four leaves on the plant. For the remainder of the summer, keep the plant growing strong until the foliage naturally yellows. In cold areas remove the corms before frost hits, then dig and clean corms, removing the old corm and saving the new one. Store in mesh bags in a well-ventilated, cool (35 to 50 degrees F.) room.

Tuberose Begonias

Tuberose Begonia

Unlike their smaller-flowered cousins, tuberous begonia plants produce 8-inch-diameter, camellia-shaped flowers in colors ranging from white to deep crimson. Tuberous begonias like it cool. They grow best under humid, cool conditions in part shade. While often grown in hanging baskets, they look equally at home in a shady bed in the ground. The frilly 'Double Pastel', the multi-colored 'Picotee', and the new, fragrant 'Scentiment' are some varieties worth trying.

Plant in containers or in the ground 8 to 12 inches apart. Keep the soil moist, but not wet. Tuberous begonias rot easily. Since the tubers are only hardy to USDA zone 9, dig them before a frost and let the tubers dry. Store them in a cool (35 to 45 degrees F.) location in dry peat moss.